Radio frequency front-end module, antenna device, and control method for radio frequency front-end module

This application claims the priority of China Patent Application No. 202110351974.4, filed on Mar. 31, 2021, entitled “Radio frequency front-end module, antenna device, and control method for radio frequency front-end module”, the contents of which are incorporated herein by reference in their entirety.

The application relates to that field of wireless communication systems of communication terminal, in particular to an antenna device on communication terminal, and further relates to a radio frequency front-end module in antenna device.

With the rapid development of mobile communication technology, wireless communication is realized on communication terminals through built-in antenna devices. With the development and application of the fifth generation mobile communication technology (5G), smart devices, especially the 5G technology in mobile terminals, are facing new challenges. The realization of technical advantages such as faster network transmission speed, greater network carrying capacity and lower network delay in 5G technology requires further optimization of 5G antenna technology. Existing antenna devices generally include baseband module, RF transceiver module, RF front-end module and antenna link module. In the application of 5G technology in mobile terminals, MIMO has become a more important technology.

MIMO is to greatly improve the channel capacity. Multiple antennas are used at both the transmitter and receiver, and a multi-channel antenna system is formed between the transmitter and receiver. However, due to the use of multiple antennas, it can transmit and receive RF signals using 1TNR mode, but when it receives RF signals at the same time, the isolation effect of multiple RF signals at the antenna switch selection module is poor, which often leads to the phenomenon of signal interference.

For example, the structure of the existing common 1T2R is shown in, including an antenna switch selection module, an RF signal composite transceiver link and a second RF signal receiving link C. The antenna switch selection moduleincludes a switch circuit, an inner peripheral port and an outer peripheral port; the switch circuit is arranged between the inner peripheral port and the outer peripheral port; the inner peripheral port includes a first inner peripheral portand a second inner peripheral port; the outer peripheral port includes a first outer peripheral portand a second outer peripheral port; the RF signal composite transceiver link includes an RF signal transmitting link A and an RF frequency signal receiving link B; wherein the RF signal composite transceiver link A includes a first filter, a power amplifier, a first low noise amplifier, a first gating switch Sand a second gating switch S; the power amplifier, the first gating switch Sand the first filterform the RF signal transmitting link A, which is arranged between the RF signal transmitting port TX and the first inner peripheral port; the first low noise amplifier, the second gating switch Sand the first filterform the first RF signal receiving link B, which is arranged between the first RF signal receiving port RXand the first inner peripheral port; the second RF signal receiving link C includes a second low noise amplifierand a second filter, arranged between the second RF signal receiving port RXand second inner peripheral port; the first outer peripheral portis connected with the first main antenna ANT; the second outer peripheral portis connected with the second main antenna ANT. In this way, the RF signal transmitting link A. RF frequency signal receiving link B and second RF signal receiving link C are formed. In the switch circuit of the antenna switch selection module, the first inner peripheral portis connected with the first outer peripheral portand the second outer peripheral portrespectively, the second inner peripheral portis connected to second outer peripheral port.

The inventor(s) of the present application realized that when the RF front-end module with the above structure is adopted, if the first main antenna ANTand the second main antenna ANTreceive RF signals at the same time (the RF signals received at the same time may be RF signals of the same frequency band or RF signals of different frequency bands), the second gating switch Sis closed, the first gating switch Sis turned off, and the first inner peripheral portof the antenna switch selection moduleis in communication with the first outer peripheral port, the RF signal received by the first main antenna ANTis coupled to the first RF signal receiving link B through the first outer peripheral portand the first inner peripheral portof the antenna switch selection modulefor signal reception. The second inner peripheral portof the antenna switch selection moduleis communicated with the second outer peripheral port, when the RF signal received by the second main antenna ANTis coupled to the second RF signal receiving link C through the second outer peripheral portand the second inner peripheral portof the antenna switch selection modulefor signal reception, due to the poor isolation of the two RF signals at the antenna switch selection module, the phenomenon of signal interference often occurs.

Details of one or more embodiments of the application are set forth in the following descriptions and drawings, and other features and advantages of the application will be apparent from the descriptions, drawings and claims.

In the prior art, when the RF front-end module receives multiple RF signals at the same time, the isolation degree of the multiple RF signals at the antenna switch selection module is too low, which often leads to mutual interference of signals. In order to solve this problem, this application provides an RF front-end module, an antenna device and a control method for the RF front-end module.

In one aspect, an RF front-end module is provided, including an antenna switch selection module, an RF signal transmitting link, a first RF signal receiving link and a second RF signal receiving link;

the antenna switch selection module includes an inner peripheral port, an outer peripheral port and a switch circuit, the switch circuit is arranged between the inner peripheral port and the outer peripheral port; wherein the inner peripheral port includes a first inner peripheral port, a second inner peripheral port and a third inner peripheral port; the outer peripheral port includes a first outer peripheral port and a second outer peripheral port; the first inner peripheral port is connected with the first outer peripheral port and the second outer peripheral port via the switch circuit, and the second inner peripheral port is connected with the first outer peripheral port via the switch circuit; the third inner peripheral port is connected with the second outer peripheral port via the switch circuit; the first outer peripheral port is used for connecting a first main antenna, and the second outer peripheral port is used for connecting a second main antenna; and the first RF signal transmitting link is connected to the first inner peripheral port, the first RF signal receiving link is connected to the second inner peripheral port, and the second RF signal receiving link is connected to the third inner peripheral port.

Furthermore, the switch circuit includes a first main switch circuit arranged between the first inner peripheral port and the first outer peripheral port, a second main switch circuit arranged between the first inner peripheral port and the second outer peripheral port, a first receiving switch circuit arranged between the second inner peripheral port and the first outer peripheral port, and a second receiving switch circuit arranged between the third inner peripheral port and the second outer peripheral port.

Furthermore, the RF front-end module includes a first working mode; in the first working mode, the first receiving switch circuit is in on state, the second receiving switch circuit is in on state, the first main switch circuit is in off state, and the second main switch circuit is in off state.

Furthermore, the first main switch circuit includes a first main switch, and the first main switch is arranged between the first inner peripheral port and the first outer peripheral port; the second main switch circuit includes a second main switch, and the second main switch is arranged between the first inner peripheral port and the second outer peripheral port.

Furthermore, the first main switch circuit further includes a first pull-down switch circuit, the first pull-down switch circuit is arranged between a connection node of the first main switch and the first outer peripheral port and a ground; the first pull-down switch circuit includes a first pull-down switch, a first matching switch and a first matching resistor;

a first end of the first pull-down switch is connected to a node between the first main switch and the first outer peripheral port, a second end of the first pull-down switch is connected with the first matching switch and the first matching resistor respectively, another end of the first matching switch is connected with the ground, and another end of the first matching resistor is connected with the ground;

the second main switch circuit further includes a second pull-down switch circuit, the second pull-down switch circuit is arranged between a node of the second main switch and the second outer peripheral port and the ground; the second pull-down switch circuit includes a first pull-down switch, a second matching switch and a second matching resistor; and a first end of the second pull-down switch is connected to a node between the second main switch and the second outer peripheral port, a second end of the second pull-down switch is connected with the second matching switch and the second matching resistor respectively, another end of the second matching switch is connected with the ground, and another end of the second matching resistor is connected with the ground.

Furthermore, the first receiving switch circuit includes a first receiving switch and a third pull-down switch, the first receiving switch is arranged between the second inner peripheral port and the first outer peripheral port, and the third pull-down switch is arranged between the second inner peripheral port and the ground.

Furthermore, the second receiving switch circuit includes a second receiving switch and a fourth pull-down switch, the second receiving switch is arranged between the third inner peripheral port and the second outer peripheral port, and the fourth pull-down switch is arranged between the third inner peripheral port and the ground.

Furthermore, the antenna switch selection module further includes a first extension outer peripheral port and a second extension outer peripheral port;

a first extension switch circuit is arranged between the first extension outer peripheral port and the first inner peripheral port, a second extension switch circuit is arranged between the second extension outer peripheral port and the first inner peripheral port;

the first extension switch circuit includes a first extension switch and a fifth pull-down switch; the first extension switch is arranged between the first inner peripheral port and the first extension outer peripheral port, and the fifth pull-down switch is arranged between the first inner peripheral port and the ground; and the second extension switch circuit includes a second extension switch and a sixth pull-down switch; the second extension switch is arranged between the first inner peripheral port and the second extension outer peripheral port, and the sixth pull-down switch is arranged between the first inner peripheral port and the ground.

Furthermore, the antenna switch selection module further includes a first extension inner peripheral port and a second extension inner peripheral port;

a third extension switch circuit is arranged between the first extension inner peripheral port and the first outer peripheral port, a fourth extension switch circuit is arranged between the first extension inner peripheral port and the second outer peripheral port;

a fifth extension switch circuit is arranged between the second extension inner peripheral port and the first outer peripheral port, a sixth extension switch circuit is arranged between the second extension inner peripheral port and the second outer peripheral port;

the third extension switch circuit includes a third extension switch and a seventh pull-down switch; the third extension switch is arranged between the first extension inner peripheral port and the first outer peripheral port, and the seventh pull-down switch is arranged between the first extension inner peripheral port and the ground;

the fourth extension switch circuit includes a fourth extension switch and an eighth pull-down switch; the fourth extension switch is arranged between the first extension inner peripheral port and the second outer peripheral port, and the eighth pull-down switch is arranged between the first extension inner peripheral port and the ground;

the fifth extension switch circuit includes a fifth extension switch and a ninth pull-down switch; the fifth extension switch is arranged between the second extension inner peripheral port and the first outer peripheral port, and the ninth pull-down switch is arranged between the second extension inner peripheral port and the ground; and the sixth extension switch circuit includes a sixth extension switch and a tenth pull-down switch; the sixth extension switch is arranged between the second extension inner peripheral port and the second outer peripheral port, and the tenth pull-down switch is arranged between the second extension inner peripheral port and the ground.

Furthermore, the RF signal transmitting link includes a power amplifier and a first filter, an input end of the power amplifier is connected to an RF signal input port, an output end of the power amplifier is connected to a first end of the first filter, and a second end of the first filter is connected to the first inner peripheral port;

the first RF signal receiving link includes a first low noise amplifier and a second filter; a first end of the second filter is connected to the second inner peripheral port, a second end is connected to an input end of the first low noise amplifier, and an output end of the first low noise amplifier is connected to a first RF signal output end; and the second RF signal receiving link includes a second low noise amplifier and a third filter; a first end of the third filter is connected to the third inner peripheral port, a second end is connected to an input end of the second low noise amplifier, and an output end of the second low noise amplifier is connected to a second RF signal output end.

In a second aspect of the application, an antenna device is provided, including a baseband module, an RF transceiver module, an RF front-end module and an antenna link module; the RF front-end module is described above.

In a third aspect of the application, a control method for the RF front-end module is provided, and the RF front-end module is described above. The method includes the follow steps: receiving a control signal, and controlling the switch circuit according to the control signal, so that the first RF signal transmitting link is in a disconnected mode with the first main antenna and the second main antenna, the first RF frequency signal receiving link is in a connected mode with the first main antenna, and the second RF signal receiving link is in a connected mode with the second main antenna.

Furthermore, the switch circuit includes a first main switch circuit arranged between the first inner peripheral port and the first outer peripheral port, a second main switch circuit arranged between the first inner peripheral port and the second outer peripheral port, a first receiving switch circuit arranged between the second inner peripheral port and the first outer peripheral port, and a second receiving switch circuit arranged between the third inner peripheral port and the second outer peripheral port;

the step of controlling the switch circuit according to the control signal, so that the first RF signal transmitting link is in a disconnected mode with the first main antenna and the second main antenna, the first RF frequency signal receiving link is in a connected mode with the first main antenna, and the second RF signal receiving link is in a connected mode with the second main antenna, includes:

controlling the first receiving switch circuit to be in the on state, the second receiving switch circuit to be in the on state, the first main switch circuit to be in the off state, and the second main switch circuit to be in the off state.

The antenna device and the RF front-end module thereof provided by the application adopt a manner of independently and separately setting the RF signal transmitting link, first RF signal receiving link and second RF signal receiving link. And when the RF signals are received at the same time, for the RF signals received by the first main antenna and the RF signals received by the second main antenna, the isolation is realized by adopting switch in the antenna switch selection module, so that the isolation between them is improved. When the RF front-end circuit receives multiple RF signals at the same time, the isolation effect between different RF signals at the antenna switch selection module is better than that of the RF front-end circuit in the prior art, thus further avoiding the phenomenon of signal interference.

Reference signs in the drawings are as follows:

. Antenna switch selection module;. First filter;. Second filter;. Third filter;. Power amplifier;. First low noise amplifier;. Second low noise amplifier;

. First inner peripheral port;. Second inner peripheral port;. Third inner peripheral port;. First outer peripheral port;. Second outer peripheral port; TX. RF signal transmitting port; RX. First RF signal receiving port; RX. Second RF signal receiving port; ANT. First main antenna; ANT. Second main antenna; TRX. First extension inner peripheral port; TRX. Second extension inner peripheral port; SRS_Tx. First extension outer peripheral port; SRS_Tx. Second extension outer peripheral port; S. First gating switch; S. Second gating switch; S. First main switch; S. First matching switch; S. First pull-down switch; R. First matching resistor; S. Second main switch; S. Second matching switch; S. Second pull-down switch; R. Second matching resistor; S. First receiving switch; S. Third pull-down switch; S. Second receiving switch; S. Fourth pull-down switch; S. First extension switch; S. Fifth pull-down switch; S. Second extension switch; S. Sixth pull-down switch; S. Third extension switch; S. Seventh pull-down switch; S. Fourth extension switch; S. Eighth pull-down switch; S. Fifth extension switch; S. Ninth pull-down switch; ST. Sixth extension switch; ST. Tenth pull-down switch.

In order to make the technical problems, technical solutions and beneficial effects of the present application more clear, the application will be further explained in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described here are only used to illustrate the application, rather than to limit the application.

In the description of the present application, it is to be understood that the terms “longitudinal”, “radial”, “length”, “width”, “thickness”, “upper”, “lower”, “front”, “rear”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inner”, “outer”, and the like indicate an orientation or positional relationship based on that shown in the drawings, and are for convenience of description and simplicity of description only, not intended to indicate or imply that the indicated devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be construed as limiting the present application.

In the description of the present application, unless otherwise stated, “multiple” means two or more. In the description of the present application, it should be noted that unless otherwise specified and defined, the terms “installation”, “connected with” and “connected to” should be understood in a broad sense. For example, they may be fixedly connected, detachably connected or integrally connected, or may be mechanically connected or electrically connected, or may be directly connected or indirectly connected through an intermediate medium. Or it may be internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application may be understood in specific situations.

This embodiment will specifically explain the communication terminal, antenna device and RF front-end module disclosed in this application. The communication terminal and antenna device of the present application are as described in the background. Communication terminal includes antenna device. Certainly, communication terminal includes not only antenna device, but also other modules, such as processors, user interfaces and memories. Communication terminal is, for example, a personal digital assistant (PDA), a mobile phone, a card in a notebook computer, a wireless tablet computer, etc. The antenna device includes a baseband module, RF transceiver module, RF front-end module and antenna link module, etc. Its overall framework is similar to that described in the background. The antenna device in this embodiment includes a baseband module, RF transceiver module, RF front-end module and antenna link module. The baseband module is used for performing digital baseband signal processing and encoding and decoding the digital baseband signal. The RF transceiver module is used for performing conversion between digital baseband and analog RF signals, processing the digital baseband signals sent by the baseband module into RF analog signals and sending them to the RF front-end module, or receiving the RF analog signals transmitted by the RF front-end module, converting them into digital baseband signals and sending them to the baseband module. The RF front-end module chooses to send RF analog signals to the antenna link module, or receive RF analog signals from the antenna link module, so as to realize amplification, filtering and other processing of the RF analog signals. The antenna link module includes an external antenna to receive or send RF analog signals. The above modules are well known to the public. The main innovative point of this application is to improve the RF front-end module, therefore the baseband module, RF transceiver module, antenna link module and so on are not explained in detail, only the RF front-end module will be explained in detail below.

The RF front-end module provided by this application will be explained in detail with the attached drawings, as shown in, including antenna switch selection module, an RF signal transmitting link A, a first RF signal receiving link B and a second RF signal receiving link C.

The antenna switch selection moduleincludes an inner peripheral port, an outer peripheral port and a switch circuit, the switch circuit is arranged between the inner peripheral port and the outer peripheral port; wherein the inner peripheral port includes a first inner peripheral port, a second inner peripheral portand a third inner peripheral port; the outer peripheral port includes a first outer peripheral portand a second outer peripheral port; the first inner peripheral portis connected with the first outer peripheral portand the second outer peripheral portvia the switch circuit, and the second inner peripheral portis connected with the first outer peripheral portvia the switch circuit; the third inner peripheral portis connected with the second outer peripheral portvia the switch circuit; the first outer peripheral portis used for connecting a first main antenna ANT, and the second outer peripheral portis used for connecting a second main antenna ANT; and

The RF signal transmitting link A, the first RF signal receiving link B and the second RF signal receiving link C are separately connected to the first inner peripheral port, the second inner peripheral portand the third inner peripheral portrespectively. That is, the first RF signal transmitting link A is connected to the first inner peripheral port, the first RF signal receiving link B is connected to the second inner peripheral port, and the second RF signal receiving link C is connected to the third inner peripheral port.

Specifically, as shown in, the RF signal transmitting link in this embodiment includes a power amplifierand a first filter. The first filteris connected to the first inner peripheral port, and an input end of the power amplifieris connected to an RF signal input port. Specifically, the input end of the power amplifieris connected to the RF signal input port, the output end of the power amplifier is connected to the first end of the first filter, and the second end of the first filteris connected to the first inner peripheral port.

The first RF signal receiving link includes a first low noise amplifierand a second filter; the second filteris connected to the second inner peripheral port, and an output end of the first low noise amplifieris connected to the first RF signal input end. Specifically, a first end of the second filteris connected to the second inner peripheral port, a second end is connected to an input end of the first low noise amplifier, and the output end of the first low noise amplifieris connected to the first RF signal output end.

The second RF signal receiving link includes a second low noise amplifierand a third filter; the third filteris connected to the third inner peripheral port, and an output end of the second low noise amplifieris connected to the second RF signal input end. Specifically, a first end of the third filteris connected to the third inner peripheral port, a second end is connected to an input end of the second low noise amplifier, and the output end of the second low noise amplifieris connected to the second RF signal output end.

The above-mentioned first low noise amplifierand second low noise amplifierrefer to amplifiers with very low noise figure. When amplifying a weak signal, the noise of the amplifier itself may interfere with the signal seriously, so it is hoped to reduce the noise of the amplifier itself to improve the signal-to-noise ratio of the output. The above low noise amplifier is well known to those skilled in the art, which could further amplify the received RF signal and output it to the RF transceiver module. Each of the first low noise amplifierand the second low noise amplifiermay be a single chip or integrated into one chip.

Power amplifieris an important part of the RF front-end module, and the output RF signal power in the RF transceiver module is very small. As one of the ports in the RF power amplifier module, the input end of the power amplifieris used to receive the RF signal transmitted by the RF transceiver module. Because the power of the RF signal output by the RF transceiver module is very small, it needs a series of amplification to obtain enough RF power before it can be fed to the antenna for radiation. In order to obtain enough RF output power, power amplifiermust be adopted, which is also well known to those skilled in the art and will not be elaborated here.